The present invention relates to an inner core structure of a rotary transformer-type resolver and, more particularly, to an inner core structure of a resolver that permits separation of a resolver rotor to permit automatic winding of the resolver rotor.
As shown in FIG. 11, a typical resolver rotor was constructed by pieces in which only a rotor body 52 was layered and press-worked. FIG. 6 is derived from Japanese Unexamined Patent Application Publication H8-279424. For the bushing 53 and transformer body 54, cutting from round bars was performed, and final finishing of the outer diameter of the entire rotor was performed by machining. Because the bushing 53 and the transformer body 54 are machined from round bars, the outer diameter of the entire rotor assembly is highly processed. After the rotor body 52 and transformer body 54 were bonded to a shaft 51, machining of the outer diameter of the entire rotor assembly was required. Thus, with the assembly of FIG. 6, it is extremely difficult to reduce costs and to automate manufacturing.
In order to solve these problems, as shown in FIG. 7, which is derived from Japanese Unexamined Patent Application Publication H8-279424, a rotor assembly was developed that included a layered rotor body 200, a layered bushing 300 and a layered transformer body 400. The layered parts were all formed by layering press-worked pieces on a shaft 100, and the respective layered parts were fastened together by means of a crimping portion 500 formed at the end of the shaft 100. This reduces the amount of machining required and reduces costs.
However, the rotor assembly shown in FIG. 7 is such that the layered rotor body 200, the layered bushing 300 and the layered transformer body 400 are formed as a unit, so when an attempt is made to use an automatic winding machine to wind the excitation windings to the layered rotor body 200, the layered transformer body 400 becomes an obstruction, and it is difficult or impossible to use an automatic winding machine. Alternatively, a special jig may be required for automatic winding.